@mixin linePoint($lineColor: #fff, $length: 30px, $gap: 20px, $stroke: 3px) {
  --x: 0px; /* 图片左上角的横坐标，动态*/
  --y: 0px; /* 图片左上角的纵坐标，动态*/
  --s: 250px; /* 图片的尺寸，动态*/
  // $half: calc(var(--s) / 2 - $gap);
  // @if ($length > $half) {
  //   $length: $half;
  // }
  position: absolute;
  box-sizing: border-box;
  width: calc(var(--s) + $gap * 2);
  height: calc(var(--s) + $gap * 2);
  border: $stroke solid $lineColor;
  top: calc(var(--y) - $gap);
  left: calc(var(--x) - $gap);
  transition: all 0.3s ease;
  cursor: pointer;
  mask: conic-gradient(at $length $length, transparent 75%, $lineColor 75%) 0 0 /
    calc(100% - $length) calc(100% - $length) repeat;
}
